Immobilization of Inulinase on Concanavalin A-Attached Super Macroporous Cryogel for Production of High-Fructose Syrup

In this study, concanavalin A (Con A)-attached poly(ethylene glycol dimethacrylate) [poly(EGDMA)] cryogels were used for immobilization of Aspergillus niger inulinase. For this purposes, the monolithic cryogel column was prepared by radical cryocopolymerization of EGDMA as a monomer and N,N′-methylene bisacrylamide as a crosslinker. Then, Con A was attached by covalent binding onto amino-activated poly(EGDMA) cryogel via glutaraldehyde activation. Characterization of cryogels was performed by FTIR, EDX, and SEM studies. Poly(EGDMA) cryogels were highly porous and pore size was found to be approximately 50–100 μm. Con A-attached poly(EGDMA) cryogels was used in the adsorption of inulinase from aqueous solutions. Adsorption of inulinase on the Con A-attached poly(EGDMA) cryogel was performed in continuous system and the effects of pH, inulinase concentration, and flow rate on adsorption were investigated. The maximum amount of inulinase adsorption was calculated to be 27.85 mg/g cryogel at 1.0 mg/mL inulinase concentration and in acetate buffer at pH 4.0. Immobilized inulinase was effectively used in continuous preparation of high-fructose syrup. Inulin was converted to fructose in a continuous system and released fructose concentration was found to be 0.23 mg/mL at the end of 5 min of hydrolysis. High-fructose content of the syrup was demonstrated by thin layer chromatography.     

A Crosslinked Carboxylic Acid Containing Cation Exchange Monolithic Cryogel for Human Serum Albumin Separation

For this work, we synthesized poly(N-isopropylacrylamide-acrylamide)-acrylic acid (poly(NIPAM-Am)-AAc) monolithic cryogel for a human serum albumin separation (HSA) from a protein mixture (human serum immunoglobulin, human serum albumin and lysozyme) and performed HSA adsorption studies using the cryogel to do continuous system experiments in a syringe column connected by a peristaltic pump. Poly(NIPAM-Am)-AAc with a pore size of 10–100 μm was produced by free radical polymerization that proceeded in an aqueous solution of monomers frozen inside a syringe column. The monolithic poly(NIPAM-Am)-AAc cryogel was characterized by performing swelling studies, FTIR and SEM that showed a swelling ratio of 6.2 g H₂O/g dry cryogel. The maximum HSA adsorption by the cryogel was 42.5 mg/g polymer at pH 4.0 in a 50 mM acetate buffer. We also studied the effect of two different temperatures (25 and 40°C). The higher temperature increased the adsorption capacity of the cryogel. HSA molecules could be reversibly adsorbed and desorbed five times with the same poly(NIPAM-Am)-AAc cryogel without a noticeable loss of their HSA adsorption capacity. The synthesized cryogel was used to separate albumin from the protein mixture. Adsorbed albumin was eluted by changing the pH of the buffer (pH 7.0 and 25°C). Poly(NIPAM-Am)-AAc monolithic cryogel behaved as a cation exchange column because of its functional carboxylic group.     

DNA adsorption via Co(II) immobilized cryogels

The separation and purification of important biomolecule deoxyribonucleic acid (DNA) molecules are extremely important. The adsorption technique among these methods is highly preferred as the adsorbent cryogels are pretty much used due to large pores and the associated flow channels. In this study, the adsorption of DNA via Co(II) immobilized poly(2-hydroxyethyl methacrylate-glycidyl methacrylate) [poly(HEMA-GMA)] cryogels was performed under varying conditions of pH, interaction time, initial DNA concentration, temperature, and ionic strength. For the characterization of cryogels; swelling test, Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), surface area (BET), elemental and ICP-OES analysis were performed. L-lysine amino acid was chosen as Co(II)-chelating agent and the adsorption capacity of cryogels was determined as 33.81 mg DNA/g cryogel. Adsorption of pea DNA was studied under the optimum adsorption conditions and DNA adsorption capacity of cryogels was found as 10.14 mg DNA/g cryogel. The adsorption process was examined via Langmuir and Freundlich isotherm models and the Langmuir adsorption model was determined to be more appropriate for the DNA adsorption onto cryogels.     

Poly(HEMA-co-NBMI) Monolithic Cryogel Columns for IgG Adsorption

Supermacroporous poly(2-hydroxyethyl methacrylate-co-1,5-naphthalene bismaleimide) [poly(HEMA-co-NBMI)] monolithic cryogel column was prepared by free radical cryo-copolymerization of HEMA with NBMI as a hydrophobic functional comonomer and N,N′-methylene-bisacrylamide as cross-linker directly in a plastic syringe for adsorption of albumin. The monolithic cryogel contained a continuous polymeric matrix which has interconnected pores of 10–100 μm size. Poly(HEMA-co-NBMI) cryogel was characterized by swelling studies, FTIR and scanning electron microscopy. The equilibrium swelling degree of the poly(HEMA-co-NBMI) cryogel was 10.5 g of H₂O/g dry cryogel. Poly(HEMA-co-NBMI) cryogel was used in the adsorption/desorption of IgG from aqueous solutions. The maximum amount of IgG adsorption from aqueous solution in phosphate buffer was 98.20 mg/g polymer at pH 7.0. The nonspecific adsorption of IgG onto plain poly(HEMA) cryogel was very low (2.79 g/g polymer). It was observed that IgG could be repeatedly adsorbed and desorbed with the poly(HEMA-co-NBMI) cryogel without significant loss of adsorption capacity.     

A novel support for antibody purification: Fatty acid attached chitosan beads

Linoleic acid attached chitosan beads [poly(LA-Ch)] (1.25 μm in diameter) are obtained by the formation of amide linkages between linoleic acid and chitosan. Poly(LA-Ch) beads are characterized by FTIR, TEM, and swelling studies. Poly(LA-Ch) beads are used for the purification of immunoglobulin-G (IgG) from human plasma in a batch system. The maximum IgG adsorption is observed at pH 7.0 for HEPES buffer. IgG adsorption onto the plain chitosan beads is found to be negligible. Adsorption values up to 136.7 mg/g from aqueous solutions are obtained by poly(LA-Ch) beads. IgG adsorption saw an increase as a result of increasing temperature. Higher amounts of IgG are adsorbed from human plasma (up to 390 mg/g) with a purity of 92%. The adsorption phenomena appeared to follow a typical Langmuir isotherm. It is observed that IgG could be repeatedly adsorbed and desorbed without significant loss when we take into account the adsorption amount. It is concluded that the poly(LA-Ch) beads allowed one-step purification of IgG from human plasma.     

Combined protein A imprinting and cryogelation for production of spherical affinity material

Cryogels have been demonstrated to be efficient when applied for protein isolation. Owing to their macroporous structure, cryogels can also be used for treating particle‐containing material, e.g. cell homogenates. Another challenging development in protein purification technology is the use of molecularly imprinted polymers (MIPs). These MIPs are robust and can be used repeatedly. The paper presents a new technology that combine the formation of cryogel beads concomitantly with making imprints of a protein. Protein A was chosen as the print molecule which was also be the target in the purification step. The present paper describes a new method to produce protein‐imprinted cryogel beads. The protein‐imprinted material was characterized and the separation properties were evaluated with regard to both the target protein and whole cells with target protein exposed on the cell surface. The maximum protein A adsorption was 18.1 mg/g of wet cryogel beads. The selectivity coefficient of protein A‐imprinted cryogel beads for protein A was 5.44 and 12.56 times greater than for the Fc fragment of IgG and protein G, respectively.     

Preparation of supermacroporous cryogels with improved mechanical strength for efficient purification of lysozyme from chicken egg white

A novel, facile, and robust strategy was proposed to increase the pore size and mechanical strength of cryogels. By mixing the monomers of acrylamide and 2‐hydroxyethyl methacrylate as the precursor, a monolithic copolymer cryogel with large interconnected pores and thick pore walls was prepared. Hydrogen bonding between the two monomers contributed to the entanglement and aggregation of the copolymers, thickening the pore walls and resulting in larger pore sizes. Analysis via mercury porosimetry demonstrated that the interconnected pore diameter of the copolymer cryogel ranged from 10‐350 µm, which was far larger than that of the cryogels from one monomer (10‐50 µm). Additionally, the thicker pore walls of the copolymer cryogel improved its mechanical strength. Affinity cryogels were prepared through covalent immobilization using Tris(hydroxymethyl)aminomethane as a coupling agent, and the affinity binding of lysozymes on Tris‐cryogel was evaluated by the Langmuir isothermal adsorption with the maximum adsorption capacity of 360 mg/g. Compared with that of the Tris‐cryogels produced from one monomer, the copolymer Tris‐cryogel exhibited higher adsorption capacity and lysozyme purity, when the chicken egg white solution flowed solely driven by gravity. This work provides a new avenue for designing and developing supermacroporous cryogels for bioseparation.     

Preparation of agarose/chitosan composite supermacroporous monolithic cryogels for affinity purification of glycoproteins

Supermacroporous agarose/chitosan composite monolithic (AC CM) cryogels were prepared for affinity purification of the major egg white glycoproteins, ovalbumin (OVA), and ovotransferrin (OVT). The supermacroporous AC CM cryogels were produced by cryocopolymerization of agarose/chitosan blend solutions using glutaraldehyde as the cross-linker. The 3-aminophenlyboronic acid ligand was immobilized by covalent binding to epoxy-group-coupled supermacroporous AC CM cryogels. The microstructure morphologies of these cryogels were analyzed by scanning electron microscopy. The supermacroporous AC CM cryogels contained a continuous interpenetrating polymer network matrix with interconnected pores of 10-100 μm in size. The composite cryogels offered high mechanical stability and had specific recognition for glycoproteins. The maximum binding capacity of OVA adsorption from aqueous solutions was 55.6 mg/g. The matrix could be reused 11 times without significant loss in OVA adsorption capacity. The recovery yields of OVA and OVT from egg white were estimated to be 89 and 93%, respectively.     

A novel adsorbent for protein chromatography: supermacroporous monolithic cryogel embedded with Cu2+-attached sporopollenin particles

The aim of this study is to prepare supermacroporous cryogels embedded with Cu(2+)-attached sporopollenin particles (Cu(2+)-ASP) having large surface area for high protein adsorption capacity. Supermacroporous poly(2-hydroxyethyl methacrylate) (PHEMA)-based monolithic cryogel column embedded with Cu(2+)-ASP was prepared by radical cryo-copolymerization of 2-hydroxyethyl methacrylate (HEMA) with N,N'-methylene-bis-acrylamide (MBAAm) as cross-linker directly in a plastic syringe for affinity purification of human serum albumin (HSA). Firstly, Cu(2+) ions were attached to sporopollenin particles (SP), then the supermacroporous PHEMA cryogel with embedded Cu(2+)-ASP was produced by free radical polymerization using N,N,N',N'-tetramethylene diamine (TEMED) and ammonium persulfate (APS) as initiator/activator pair in an ice bath. Embedded particles (10 mg) in PHEMA-based cryogel column were used in the adsorption/desorption of HSA from aqueous solutions. Optimum conditions of adsorption experiments were performed at pH 8.0 phosphate buffer, with flow rate of 0.5 mL/min, and at 5°C. The maximum amount of HSA adsorption from aqueous solution was very high (677.4 mg/g SP) with initial concentration 6 mg/mL. It was observed that HSA could be repeatedly adsorbed and desorbed to the embedded Cu(2+)-ASP in PHEMA cryogel without significant loss of adsorption capacity.     

The effect of NaCl on the adsorption of human IgG onto CM-Asp–PEVA hollow fiber membrane-immobilized nickel and cobalt metal ions

Over the past decade, immobilized metal-affinity adsorbents have attracted increasing interest for purification of natural and recombinant immunoglobulin G (IgG). In this work, nickel and cobalt metal ions complexed with CM-Asp (carboxymethylaspartate) immobilized on poly(ethylenevinyl alcohol) (PEVA) hollow fiber membranes were evaluated for purification of human IgG from serum. The buffer system and NaCl had important effects on human serum protein adsorption in both adsorbents. Efficient purification of IgG was accomplished in sodium phosphate buffer without NaCl at pH 7.0. Under this condition, the electrostatic interactions are important for adsorption. The Ni(II)-CM-Asp–PEVA had a protein adsorption capacity of 17.5 mg of IgG mL^?1 fiber when human serum diluted was loaded in crossflow filtration mode and the eluted IgG had a purity of 82.6 % (based on total protein and IgG, IgM, HSA, and Trf nephelometric analysis). Fitting the experimental IgG adsorption data to the Langmuir and Langmuir–Freundlich models showed that Ni(II)-CM-Asp and Co(II)-CM-Asp had Langmuirean and non-Langmuirean behavior, respectively, with positive cooperativity for IgG-Co(II)-CM-Asp binding, probably due to multipoint interactions (n = 2.12 ± 0.31). Thus, these membranes can be considered as alternative adsorbents for the purification or depletion of IgG from human serum.     

Hydrophobic cryogels for DNA adsorption: Effect of embedding of monosize microbeads into cryogel network on their adsorptive performances

As alternative hydrophobic adsorbent for DNA adsorption, supermacroporous cryogel disks were synthesized via free radical polymerization. In this study, we have prepared two kinds of cryogel disks: (i) poly(2‐hydroxyethyl methacrylate‐N‐methacryloyl‐l ‐tryptophan) [p(HEMA‐MATrp)] cryogel containing specific hydrophobic ligand MATrp; and (ii) monosize p(HEMA‐MATrp) particles synthesized via suspension polymerization embedded into p(HEMA) cryogel structure to obtain p(HEMA‐MATrp)/p(HEMA) composite cryogel disks. These cryogel disks containing hydrophobic functional group were characterized via swelling studies, Fourier transform infrared spectroscopy, elemental analysis, surface area measurements and scanning electron microscopy. DNA adsorption onto both p(HEMA‐MATrp) cryogel and p(HEMA‐MATrp)/p(HEMA) composite cryogels was investigated. Maximum adsorption of DNA on p(HEMA‐MATrp) cryogel was found to be 15 mg/g polymer. Otherwise, p(HEMA‐MATrp)/p(HEMA) composite cryogels significantly increased the DNA adsorption capacity to 38 mg/g polymer. Composite cryogels could be used repeatedly without significant loss on adsorption capacity after 10 repetitive adsorption–desorption cycles. Copyright © 2013 John Wiley & Sons, Ltd.     

Chemical Modification of Ethyl Cellulose-Based Highly Porous Membrane for the Purification of Immunoglobulin G

The chemical modification of developed ethyl cellulose-based membrane was carried out to make it suitable for bioseparation. The different reagents were used for the modification of membrane to couple protein A (PA) to study the purification of immunoglobulin G (IgG) from blood. The chemical modification was carried out using relatively simple and mild reaction conditions. The attenuated total reflectance Fourier transform infrared analysis of chemically modified membrane showed new peak at 1,596.06 and 1,716.49 cm^?1. The scanning electron microscopy of PA-coupled membrane, which was used for IgG purification showed open pores and 950?±?21.5 LMH (L?m^?2?h^?1) operational flux at 0.5-bar out pressure. The flux of unmodified membrane was 1,746?±?18.5 LMH at 0.5-bar out pressure. The equilibrium adsorption concentration (318.5?±?5.9 μg?cm^?2) was obtained at 3 h. The adsorption character of PA-coupled membrane was consistent with the Langmuir adsorption model and the non-specific binding was 67.08?±?1.3 μg?cm^?2. The sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis showed similar purification pattern for purified IgG from human serum and commercial preparation of IgG. All the results have suggested a high potential of PA-coupled ethyl cellulose-based membrane for large-scale purification of IgG.     

Synthesis of phosphorus-modified poly(styrene-co-divinylbenzene) chelating resin and its adsorption properties of uranium(VI)

A new phosphorus-modified poly(styrene-co-divinylbenzene) chelating resin (PS–N–P) was synthesized by P,P-dichlorophenylphosphine oxide modified commercially available ammoniated polystyrene beads, and characterized by Fourier transform infrared spectroscopy and elemental analysis. The adsorption properties of PS–N–P toward U(VI) from aqueous solution were evaluated using batch adsorption method. The effects of the contact time, temperature, pH and initial uranium concentration on uranium(VI) uptake were investigated. The results show that the maximum adsorption capacity (97.60 mg/g) and the maximum adsorption rate (99.72 %) were observed at the pH 5.0 and 318 K with initial U(VI) concentration 100 mg/L and adsorbent dose 1 g/L. Adsorption equilibrium was achieved in approximately 4 h. Adsorption kinetics studied by pseudo second-order model stated that the adsorption was the rate-limiting step (chemisorption). U(VI) adsorption was found to barely decrease with the increase in ionic strength. Equilibrium data were best modeled by the Langmuir isotherm. The thermodynamic parameters such as ?G ₀, ?H ₀ and ?S ₀ were derived to predict the nature of adsorption. Adsorbed U(VI) ions on PS–N–P resin were desorbed effectively (about 99.39 %) by 5 % NaOH–10 % NaCl. The synthesized resin was suitable for repeated use.     

Superior magnetic monodisperse particles for direct purification of immunoglobulin G under magnetic field

Monodisperse magnetic acrylate based particles (5.0 µm in diameter) containing histidine were synthesized using a modified suspension polymerization method for the purification of immunoglobulin G from human plasma in a magnetically stabilized fluidized bed. N-methacryloyl-(L)-histidine methyl ester (MAH) was used as pseudo-specific ligand/co-monomer. MAH content of the magnetic particles was calculated as 55.3 µmol MAH/g polymer using elemental analysis. Immunoglobulin G binding amount of the magnetic particles decreased with increase of the flow-rate. The maximum immunoglobulin G binding was observed at pH 7.4 (phosphate buffer). Immunoglobulin G binding amount onto the magnetic poly(ethylene glycol dimethacrylate) [mPEGDMA] particles was found to be almost negligible due to the hydrophilic polymer structure. High binding values were obtained from aqueous solutions (1646 mg/g). Higher immunoglobulin G binding was observed when human plasma was used (2169 mg/g). Purity of the separated immunoglobulin G from human plasma was found to be 87%. Magnetic PEGDMAH particles could be used many times without significant loss in protein binding amount.     

Adsorption of phenol in flow systems by a monolithic carbon cryogel with a microhoneycomb structure

Adsorption of phenol from an aqueous solution in batch and continuous flow systems using carbon gels with a microhoneycomb structure (carbon gel microhoneycombs, CMHs) was studied. The obtained monolithic CMHs had fairly straight channels, 25–45 μm in diameter, and the thickness of the walls which form the channels was around 5 μm. The CMHs showed 370 times lower hydraulic resistance when compared with a column packed with particles having the same diffusion path length as it. The obtained CMHs have a hierarchical micro-meso porous structure giving BET surface area in the range of 513–1070 m²·g^?1.When used for phenol adsorption from an aqueous solution, the CMHs quickly adsorbed phenol at first, and then, the uptake gradually increased, which indicates that the adsorption mechanism is based on not only simple physisorption. The phenol adsorption capacity increased with the increase in carbonization temperature of the CMH and the decrease in its hydrophilicity. CMHs carbonized at temperatures higher than 1073 K showed the highest phenol adsorption capacity which was around 160 mg·g^?1. The CMHs could continuously adsorb phenol from aqueous solutions, and their length of unused bed (LUB) values depended on operation conditions but were in the range of 0.3–0.7 cm. The experimental results indicated that carbon cryogels with a microhoneycomb structure have a high potential to be used for effective separation of phenol.     

Synthesis and characterisation of nanofibrillar cellulose aerogels

We prepared from cellulose fibres monolithic aero- and cryogels. Cellulose is dissolved in hydrated calciumthiocyanate melt, gelled, aged and dried by several methods. The density of cellulose aerogels produced by supercritical drying is in the range between 10 and 60 kg/m³ with a surface area of 200–220 m²/g. The cellulose cryogels produced by freeze drying exhibit a maximum surface area of 160 m²/g. Sputtered cellulose aero- and cryogels are examined with a scanning electron microscope. The results are discussed with respect to the literature and simple mathematical models.     

Heavy Metal Removal from Synthetic Solutions with Magnetic Beads Under Magnetic Field

The aim of this study is to prepare magnetic beads which can be used for the removal of heavy metal ions from synthetic solutions. Magnetic poly(ethylene glycol dimethacrylate‐vinyl imidazole) [m‐poly(EGDMA‐VIM)] beads were produced by suspension polymerization in the presence of magnetite Fe₃O₄ nano‐powder. The specific surface area of the m‐poly(EGDMA‐VIM) beads was found to be 63.1 m²/g with a size range of 150–200 µm in diameter and the swelling ratio was 85%. The average Fe₃O₄ content of the resulting m‐poly(EGDMA‐VIM) beads was 12.4%. The maximum binding capacities of the m‐poly(EGDMA‐VIM) beads were 32.4 mg/g for Cu²⁺, 45.8 mg/g for Zn²⁺, 84.2 mg/g for Cd²⁺and 134.5 mg/g for Pb²⁺. The affinity order on mass basis is Pb²⁺>Cd²⁺>Zn²⁺>Cu²⁺. Equilibrium data agreed well with the Langmuir model. pH significantly affected the binding capacity of the magnetic beads. Binding of heavy metal ions from synthetic wastewater was also studied. The binding capacities were 26.2 mg/g for Cu²⁺, 33.7 mg/g for Zn²⁺, 54.7 mg/g for Cd²⁺ and 108.4 mg/g for Pb²⁺. The magnetic beads could be regenerated up to about 97% by treating with 0.1 M HNO₃. These features make m‐poly(EGDMA‐VIM) beads a potential candidate for support of heavy metal removal under magnetic field.     

Solid-phase extraction for the simultaneous preconcentration of organic (selenocystine) and inorganic [Se(IV), Se(VI)] selenium in natural waters

The recombinantly produced different forms of protein G, namely monofunctional immunoglobulin G (IgG) binding, monofunctional serum albumin (SA) binding and bifunctional IgG/SA binding proteins G, are compared with respect to their specific affinities to blood IgG and SA. The affinity mode of the recently developed high-performance monolithic disk chromatography has been used for fast quantitative investigations. Using single affinity disks as well as two discs stacked into one separation unit, one order of magnitude in adsorption capacities for IgG and SA were found both for monofunctional and bifunctional protein G forms used as specific affinity ligands. However, despite the adsorption difference observed, the measured dissociation constants of the affinity complexes seemed to be very close. The analytical procedure developed can be realized within a couple of minutes. Up-scaling of the developed technology was carried out using another type of monolithic materials, i.e. CIM affinity tubes.     

Characterization of metal chelate methacrylate monolithic disk for purification of polyclonal and monoclonal immunoglobulin G

Dynamic binding capacity (DBC) of commercial metal-chelate methacrylate monolith-convective interaction media (CIM) was performed with commercial human immunoglobulin G (IgG) (Cohn fraction II, III). Monoliths are an attractive stationary phase for purification of large biomolecules because they exhibit very low back pressure even at high flow rates and flow-unaffected binding properties. Adsorption of IgG onto CIM-IDA disk immobilized with Cu²⁺, Ni²⁺ and Zn²⁺ were studied with Tris-acetate (TA), phosphate-acetate (PA) and MMA (MES, MOPS and acetate) buffer systems at different flow rates. Adsorption and elution of IgG varied with different buffers and adsorption of IgG was maximum with MMA buffer. Adsorption of human IgG from Cohn fractions (II, III) was high when Cu²⁺ was used as ligand. CIM-IDA disk showed dynamic binding capacity in the range of 14–16 mg/ml with Cu²⁺ and 7–9 mg/ml with Ni²⁺ for human IgG with MMA buffer. In the case of CIM-IDA-Zn²⁺ column, the binding capacity was only about 0.5 mg/ml of support. Different desorption strategies like lowering of pH and increasing of competitive agent were also studied to achieve maximum recovery. Chromatographic runs with human serum and mouse ascites fluid were also carried out with metal chelate methacrylate monolithic disk and the results indicate the potential of this technique for polyclonal human IgG and monoclonal IgG purification from complex biological samples.     

Metal-Chelating Nanopolymers for Antibody Purification from Human Plasma

The purification of immunoglobulin G (IgG) from human plasma was performed by using a novel metal-chelated adsorbent with nano size. The non-porous nanoparticles were produced by surfactant free emulsion polymerization of ethylene glycol dimethacrylate (EDMA) and 2-methacryloylamidohistidine (MAH). Then, Cu(II) ions were chelated on the nanoparticles. The nano-poly(EDMA-MAH) nanoparticles were characterized by Fourier transform infrared, scanning electron microscope, atomic force microscope and elemental analysis. The non-porous nanoparticles were spherical form and have 100?C250?nm size distribution. The maximum IgG adsorption capacity of the Cu(II) chelated nanoparticles was found to be 463?mg/g polymer at pH 7.0 in HEPES buffer. Desorption of IgG was performed by 1.0?M NaCl and desorption rate was found to be 97?%. IgG was obtained from human plasma with purity of 94?% (up to 578?mg/g polymer). The non-porous nanoparticles allowed one-step purification of IgG from human plasma.